No I don't recommend carbon, it's a waste of time in my own eyes and many other peoples. I would rather do water changes to remove medication. I would be more beneficial for the fish to have tannins from the wood in the water in most cases. Filter floss will do a much better good at getting fine particles out of water. The last point I have against it, is the cost and how often it actually needs replacing. Do a search of the forums for threads on carbons and make up your own mind on the subject.
Power heads however have their uses, I'm using power heads to keep my tanks clean as they push the waste round so the filters can pick it out. The added current is also liked by some fish who will swim against it. On the subject of helping to aerate, they do a great job due to the power of some to help add more oxygen to the water.